Giant Omega-DX (ジャイアントオメガDX,Jaianto Omega Derakkusu?, "Giant Omega Deluxe") is a giant robot from the Rockman Zero manga. Dr. Weil is not satisfied with Omega's failure to find the Dark Elf, and Omega says he is being delayed by Zero. Dr. Weil decides to give Omega three days to defeat Zero, or else he will be fired. To help him, Weil gives him the Giant Omega-DX, a robot shaped like Omega that is 10 times bigger than him. However, it needs to be assembled by Omega and his minions.

As it requires a large amount of Energy Crystals, Omega went to Lito's house at night, but Zero saw him and the two fought, Omega using his detachable flying arm to distract Zero while he escapes. Without noticing, Omega leaves a trail of Energy Crystals and Zero retrieves them, finding the place Omega was building the Giant Omega-DX. They fight and Zero destroys Omega's minions, causing Omega to start crying as Dr. Weil will surely fire him, saying he is unable to finish the construction alone and without the Energy Crystals. Zero takes pity on him and decides to help in the construction, giving the Energy Crystals for him and the two working day and night without sleeping to finish the Giant Omega-DX on time. During the construction, Zero skips many important parts to finish it faster.

Giant Omega-DX firing the Omega Laser

In the last day, Omega finishes the robot by going inside the head and attaching it to the body, activating it and trying to crush Zero with its feet, Zero barely avoiding it. Zero asks Omega what he is doing, and Omega says the robot's purpose is to destroy him. Omega starts charging the Omega Laser, but as it is preparing to fire, the robot's left leg collapses due to the missing parts and it fires the laser to the sky, exploding during the shot.